Examination of Granulosa Cell Glycoconjugates Which Change During Follicular Atresia in the Pig Ovary

Abstract

Changes of glycoconjugates in granulosa cells during follicular atresia were examined by lectin histochemical and biochemical techniques. Twenty-four lectins were used to visualize the different glycoconjugates of granulosa cells in frozen sections of the pig ovary. Four lectins showed stronger staining of the granulosa cells in atretic than in healthy follicles. Very strong and/or strong staining with Sambucus sieboldiana agglutinin (SSA) was seen in scattered granulosa cells of atretic follicles, but those of healthy follicles were not stained with this lectin. In atretic follicles, very strong-moderate diffuse staining was seen with Aleuria aurantia lectin (AAL), Pisum sativum agglutinin (PSA) and Lens culinaris agglutinin (LCA) in granulosa cells, in contrast with very weak staining in those of healthy follicles. Furthermore, lectin blot analysis with three lectins (SSA, AAL, and PSA) indicated several glycoproteins with increased staining in atretic relative to healthy follicles for these three lectins. Especially, two SSA-positive glycoproteins (62 and 64 kD) of granulosa cells in atretic follicles were specific and characteristic which were not detected in those in healthy follicles. These results suggest that changes of some glycoconjugates in granulosa cells may be involved in granulosa cell apoptosis and follicular atresia.